China’s Tiananmen Square has been swamped by security personnel on the 25th anniversary of the Beijing massacre.
Foreign journalists were ushered away from the square and passers-by were searched and had their papers checked.
In recent weeks, the authorities have detained dozens of activists to ensure their silence on the anniversary.
The 1989 protesters wanted political reform, but the crackdown was ordered after hardliners won a power struggle within the ruling Communist Party.
The authorities classify the 1989 protests as counter-revolutionary riots and hold no memorial.
In Hong Kong, however, thousands are expected to take part in a Tiananmen remembrance rally.
Activist groups in Taiwan are also marking the anniversary by erecting a huge image of Tiananmen Square during the crackdown.
In the weeks before this year’s anniversary, the Chinese authorities have detained lawyers, journalists and activists.
Rights group Amnesty International said in a statement that 66 people had been detained, questioned, or have gone missing.
Internet search terms related to the 1989 massacre and the protests have been blocked, and access on Google has reportedly been restricted.
The protests were the biggest rally against Communist rule since the People’s Republic was founded in 1949.
Hundreds of thousands called for democratic reforms in a peaceful demonstration largely focused on a gathering in Tiananmen Square.
After six weeks of protests, the authorities responded on June 4, 1989, with a massacre of hundreds in the streets of Beijing.
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